liminfoSpeed Converter
Free web tool: Speed Converter
Conversion Result
62.13711922 mph
All Conversions
m/s (meters/sec)
27.77777778
km/h (kilometers/hr)
100
mph (miles/hr)
62.13711922
ft/s (feet/sec)
91.13444153
knot
53.99572699
Mach
0.08098477486
km/s
0.02777777778
cm/min
166,666.666667
About Speed Converter
The Speed Unit Converter transforms values between 8 speed units in real time: meters per second (m/s), kilometers per hour (km/h), miles per hour (mph), feet per second (ft/s), knots, Mach number, kilometers per second (km/s), and centimeters per minute (cm/min). All conversions use the base unit m/s with SI-standard conversion factors such as 1 km/h = 1/3.6 m/s, 1 mph = 0.44704 m/s, 1 knot = 0.514444 m/s, and Mach 1 = 343 m/s at sea level.
Enter any numeric value, select source and target units, and see the converted result instantly along with a full conversion table showing all 8 units simultaneously. The swap button lets you reverse the direction in one click. Results use smart formatting with up to 10 significant digits for small values and locale-aware thousand separators for large values.
This tool is built for engineers, pilots, sailors, physicists, students, and anyone who needs quick accurate speed conversions. All computation runs entirely in your browser using JavaScript — no server round-trips, no data collection, and no account required.
Key Features
- Converts between 8 speed units: m/s, km/h, mph, ft/s, knots, Mach, km/s, cm/min
- Real-time conversion table updates all 8 units simultaneously as you type
- One-click unit swap button to reverse source and target units instantly
- SI-standard conversion factors: 0.44704 (mph), 0.514444 (knot), 343 (Mach), 0.3048 (ft/s)
- Smart number formatting with 10 significant digits and locale-aware thousand separators
- Highlighted source unit in the full conversion grid for easy reference
- Bilingual interface with full Korean and English language support
- 100% client-side calculation — no server calls, no data stored, completely private
Frequently Asked Questions
What speed units does this converter support?
The converter supports 8 units: meters per second (m/s), kilometers per hour (km/h), miles per hour (mph), feet per second (ft/s), knots, Mach number (at sea level, 343 m/s), kilometers per second (km/s), and centimeters per minute (cm/min). All conversions use m/s as the internal base unit.
How accurate are the conversion factors?
The tool uses internationally recognized SI conversion factors. For example, 1 mph = 0.44704 m/s (exact), 1 knot = 0.514444 m/s (international nautical mile per hour), 1 ft/s = 0.3048 m/s (exact), and Mach 1 = 343 m/s (speed of sound at 20 degrees C at sea level). Results are displayed with up to 10 significant digits.
What is the difference between km/h and mph?
1 km/h equals approximately 0.6214 mph. To convert km/h to mph, multiply by 0.6214 (or divide by 1.60934). This converter handles the math automatically, applying the precise factor: both units are first converted to m/s using 1 km/h = 1/3.6 m/s and 1 mph = 0.44704 m/s.
What Mach number does this tool use?
The tool uses Mach 1 = 343 m/s, which is the speed of sound in dry air at 20 degrees Celsius at sea level. In aviation, the actual Mach number varies with altitude and temperature. For standard atmosphere calculations at different altitudes, the speed of sound changes accordingly.
Why are knots used in aviation and maritime navigation?
One knot equals one nautical mile per hour (1.852 km/h or 0.514444 m/s). Nautical miles correspond to one minute of latitude, making knots convenient for navigation on charts. This converter handles knot conversions using the exact international definition.
How does the full conversion table work?
When you enter a value and select a source unit, the tool converts it to m/s first, then calculates all 8 target units simultaneously. The source unit is highlighted in blue in the grid. This lets you see, for example, that 100 km/h equals 62.1371 mph, 27.7778 m/s, 53.9957 knots, and 0.080972 Mach at once.
Can I convert very large or very small speed values?
Yes. The formatter handles extreme values gracefully: values above 1000 use locale-aware thousand separators (e.g., 299,792.458 for light speed in km/s to m/s), while very small values use up to 10 significant digits. Values below 1e-10 display as zero.
Is my input data stored or sent to a server?
No. All speed conversions are calculated entirely in your browser using JavaScript arithmetic. No network requests are made, no data is logged, and nothing is stored on any server. Your values stay on your device.